Fasting Mimicking Diet: Calorie Restriction increases Healthspan

Valter Longo, Professor of Gerontology and Professor of Biological Science at the University of Southern California, has for over 20 years explored the complex relationship between calorie restriction and good health. His recent research has further built upon our understanding of this relationship, and provided significant support for the use of a new method of calorie restriction in therapeutics.

Fasting Mimicking Diet based on Calorie Restriction found to be associated with increased healthspan.

Fasting Mimicking Diet based on Calorie Restriction found to be associated with increased healthspan.

Fasting Mimicking Diet based on Calorie Restriction found to be associated with increased healthspan.

Fasting Mimicking Diet based on Calorie Restriction found to be associated with increased healthspan.

In recent years Dr Valter Longo’s research into the relationship between human health and cyclical fasting has uncovered a startling range of positive health benefits associated with the practice; in June last year Longo showed that cyclical fasting can effectively trigger the regeneration of damaged immune systems and protect immune cells during chemotherapy, whilst in 2013 Longo published evidence that the progression of Alzheimer’s in mice can be slowed by a low-protein diet.

This year, Dr Longo has produced yet more evidence for the beneficial effects of calorie restriction – specifically a method of dietary restriction termed fasting mimicking dieting (FMD).

In a study published in July in Cell Metabolism, Longo showed that bi-monthly cycles of a restrictive diet designed to mimic fasting (FMD) resulted in “extended longevity, lowered visceral fat, reduced cancer incidence and skin lesions”, “cognitive improvements” and “immune system regeneration” in mice. Whilst in humans, 3 cycles of FMD was shown to “reduce multiple risk factors” associated with diabetes, cardiovascular disease, cancer and aging. (1)

(FIG). Summary of the health changes associated with FMD in yeast, mice and humans.

The Fasting Mimicking Diet was developed by Longo as a potentially safer, more moderate alternative to water-only fasting. The beneficial effects of prolonged, water-only fasting on human health are well documented, however it is still considered an extreme and risky dietary intervention, having the potential to cause negative effects as well as positive. FMD has therefore been designed by Longo as an effective alternative which “mimics the effects of fasting” whilst “minimizing the risk of adverse effects and the burden of complete food restriction.” (1)

The ultimate goal of Longo’s research is for FMD to be approved as a therapeutic tool; Dr Longo recently told the University of Southern California that he hopes FMD will “represent the first safe and effective intervention to promote positive changes associated with longevity and health span, which can be recommended by a physician.” (2)

One barrier to introducing fasting into the field of medicine is low patient compliance; statistics show that patients are often unable, or unwilling, to make significant, difficult life-style changes for the sake of their health. (3) Longo himself has acknowledged that “strict fasting is hard for people to stick to.” (2)

FMD, therefore, was developed not just as a safer alternative to fasting, but also an easier, and far less burdensome, alternative; whilst water-only fasting requires no caloric intake on fasting days, FMD permits individuals to eat a limited amount during each of the monthly FMD cycles (~1090 kcal on day 1, 725 kcal on days 2-5). Under these conditions Longo reported “very high compliance” amongst subjects, bolstering hopes that if FMD becomes approved as a therapeutic treatment, patient adherence will be high. (1)

FMD can also be compared favourably to traditional dieting methods, as whilst traditional diets require long-term, persistent effort, FMD only requires restricted caloric intake for 5 days a month, and allows for normal eating habits all other days.

(FIGIII). Effects of prolonged-fasting in mice, compared to non-dieting mice.

In past mouse studies, true fasting over prolonged periods has been associated with stem cell-based immune-system regeneration and immune-protection during chemotherapy and aging.

(FIGIII). Effects of prolonged-fasting in mice, compared to non-dieting mice. In past mouse studies, true fasting over prolonged periods has been associated with stem cell-based immune-system regeneration and immune-protection during chemotherapy and aging.

(FIGIII). Effects of prolonged-fasting in mice, compared to non-dieting mice. In past mouse studies, true fasting over prolonged periods has been associated with stem cell-based immune-system regeneration and immune-protection during chemotherapy and aging.

(FIGIII). Effects of prolonged-fasting in mice, compared to non-dieting mice. In past mouse studies, true fasting over prolonged periods has been associated with stem cell-based immune-system regeneration and immune-protection during chemotherapy and aging.

“It’s not a typical diet because it isn’t something you need to stay on,” explained Longo.(2)

Whilst FMD appears to be safer and easier than other, more extreme methods of fasting, Longo warns that the practice should still “only be considered for use under medical supervision,” and acknowledges that although his findings show FMD to be both effective and “generally safe” they still require “confirmation by a larger randomized trial.” (1)

Valter D. Longo, Ph.D. is a biogerontologist / cell biologist known for his studies on the role of starvation and nutrient response genes on cellular protection aging and diseases, and for proposing that longevity is regulated by similar genes and mechanisms in many eukaryotes. In addition of heading the USC Longevity Institute, Longo is also the Edna M. Jones professor of biogerontology at the USC Davis School of Gerontology with a joint appointment at the USC Dornsife College of Letters, Arts and Sciences.

Valter D. Longo, Ph.D. is a biogerontologist / cell biologist known for his studies on the role of starvation and nutrient response genes on cellular protection aging and diseases, and for proposing that longevity is regulated by similar genes and mechanisms in many eukaryotes. In addition of heading the USC Longevity Institute, Longo is also the Edna M. Jones professor of biogerontology at the USC Davis School of Gerontology with a joint appointment at the USC Dornsife College of Letters, Arts and Sciences.

Valter D. Longo, Ph.D. is a biogerontologist / cell biologist known for his studies on the role of starvation and nutrient response genes on cellular protection aging and diseases, and for proposing that longevity is regulated by similar genes and mechanisms in many eukaryotes. In addition of heading the USC Longevity Institute, Longo is also the Edna M. Jones professor of biogerontology at the USC Davis School of Gerontology with a joint appointment at the USC Dornsife College of Letters, Arts and Sciences.

Valter D. Longo, Ph.D. is a biogerontologist / cell biologist known for his studies on the role of starvation and nutrient response genes on cellular protection aging and diseases, and for proposing that longevity is regulated by similar genes and mechanisms in many eukaryotes. In addition of heading the USC Longevity Institute, Longo is also the Edna M. Jones professor of biogerontology at the USC Davis School of Gerontology with a joint appointment at the USC Dornsife College of Letters, Arts and Sciences.

Christopher Edward Jones is a biochemist and writer currently affiliated with Queen Mary University of London, where he is part of a research group focusing on the restriction factors of HIV. In the past he has worked with multiple biomedical research groups in both industry and academia. He has a research interest in the biochemical mechanisms of virus restriction and a general interest in all areas of science.

Christopher Edward Jones is a biochemist and writer currently affiliated with Queen Mary University of London, where he is part of a research group focusing on the restriction factors of HIV. In the past he has worked with multiple biomedical research groups in both industry and academia. He has a research interest in the biochemical mechanisms of virus restriction and a general interest in all areas of science.

Christopher Edward Jones is a biochemist and writer currently affiliated with Queen Mary University of London, where he is part of a research group focusing on the restriction factors of HIV. In the past he has worked with multiple biomedical research groups in both industry and academia. He has a research interest in the biochemical mechanisms of virus restriction and a general interest in all areas of science.

Christopher Edward Jones is a biochemist and writer currently affiliated with Queen Mary University of London, where he is part of a research group focusing on the restriction factors of HIV. In the past he has worked with multiple biomedical research groups in both industry and academia. He has a research interest in the biochemical mechanisms of virus restriction and a general interest in all areas of science.